Narrated Anas bin Malik:

"Once Mu'adh was along with Allah's Apostle as a companion rider. Allah's Apostle ﷺ said, "O Mu'adh bin Jabal." Mu'adh replied, "Labbaik and Sa'daik. O Allah's Apostle!" Again the Prophet ﷺ said, "O Mu'adh!" Mu'adh said thrice, "Labbaik and Sa'daik, O Allah's Apostle!" Allah's Apostle ﷺ said, "There is none who testifies sincerely that none has the right to be worshipped but Allah and Muhammad is his Apostle, except that Allah, will save him from the Hell-fire." Mu'adh said, "O Allah's Apostle ! Should I not inform the people about it so that they may have glad tidings?" He replied, "When the people hear about it, they will solely depend on it." Then Mu'adh narrated the above-mentioned Hadith just before his death, being afraid of committing sin (by not telling the knowledge).

حَدَّثَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، قَالَ حَدَّثَنَا مُعَاذُ بْنُ هِشَامٍ، قَالَ حَدَّثَنِي أَبِي، عَنْ قَتَادَةَ، قَالَ حَدَّثَنَا أَنَسُ بْنُ مَالِكٍ، أَنَّ النَّبِيَّ ﷺ وَمُعَاذٌ رَدِيفُهُ عَلَى الرَّحْلِ قَالَ " يَا مُعَاذُ بْنَ جَبَلٍ ". قَالَ لَبَّيْكَ يَا رَسُولَ اللَّهِ وَسَعْدَيْكَ. قَالَ " يَا مُعَاذُ ". قَالَ لَبَّيْكَ يَا رَسُولَ اللَّهِ وَسَعْدَيْكَ. ثَلاَثًا. قَالَ " مَا مِنْ أَحَدٍ يَشْهَدُ أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ وَأَنَّ مُحَمَّدًا رَسُولُ اللَّهِ صِدْقًا مِنْ قَلْبِهِ إِلاَّ حَرَّمَهُ اللَّهُ عَلَى النَّارِ ". قَالَ يَا رَسُولَ اللَّهِ، أَفَلاَ أُخْبِرُ بِهِ النَّاسَ فَيَسْتَبْشِرُوا قَالَ " إِذًا يَتَّكِلُوا ". وَأَخْبَرَ بِهَا مُعَاذٌ عِنْدَ مَوْتِهِ تَأَثُّمًا .